Azure App Service - Outbound IP changed
Azure App Service does not support fixed outbound IP due to its architecture considerations, instead, you have a range of IPs that could be used. To see the list of these IPs:
- select your app service
- navigate to properties
- verify the list of outbound IPs in "OUTBOUND IP ADDRESSES"
Note that you also get an external IP address if you configure a Custom Domain, but this is related to INBOUND connections only.
If you want your own set of outbound IPs or really need a fixed one, consider App Service Environment.
Update:
Are these outbound IPs guaranteed to remain the same as long as the azure web site isn’t deleted?
there is no guarantee, but they will not change from 1 day to the next, nor is there any plan or real need to change them. I have read that if this ever happens those impacted will get enough warning to make any changes to their systems to prevent any problems. They are never expected to change and you should feel comfortable that they will remain static.
https://blogs.msdn.microsoft.com/benjaminperkins/2016/03/02/how-to-find-you-outgoing-azure-app-service-ip-address/
Static Outbound IP without ASE - Still Under Review
https://feedback.azure.com/forums/169385-web-apps-formerly-websites/suggestions/16790656-add-static-ip-address-for-outbound-traffic-without